Vertical pumps locating

Fiaure 2-8B—Locations forTakina Vibration Readinas on Vertical Pumps... 

This procedure represents a preparative version of zone electrophoresis. The apparatus and technique has been previously elaborated [294,295] separation itself is carried out either in a stream of electrolytic solution or on a sheet of cardboard (curtain electrophoresis). In the free flow version the separation is carried out in a cell formed by two parallel glass plates (50 x 50 cm) situated 0.5-1.0 mm apart. It is necessary to ensure an equal and laminar flow of the electrolyte, which is carried out by feeding the buffer through a multichannel peristaltic pump. The sample is continuously applied in the middle near the upper edge of the cuvette (or paper sheet). The electrophoretic separation occurs transversally between vertical electrodes located on the right and left hand side of the separation cuvette (Fig. 6.33). The separated fractions are collected at the lower end of the cell by a system of small communicating vessels or by a multi-channel pump. In the version using paper the... 

Very small pumps, in-line or vertical pumps, are usually adjacent to their suction vessel. With many pumps taking suction from the same vessel (a crude fractionator, for example), adjacent pump location is possible with only four or six pumps. For a great number of medium or large-sized pumps, road access must be provided. It is advantageous and economical to have a common road to all the pumps in the plant for convenient operation and maintenance. Too many dead-end access roads between process equipment lengthen the yard bank. 

The primaiy coolant circulation pumps are typically internal, canned axial pumps, of the glandless, vertical mixed-flow type. Some alternate IPWR arrangements have the pumps located on nozzles or "stems" attached to the lower portion of the RPV, as in the NS Otto Hahn design, and often in the cold leg of the primaiy circuit. 

Hot leg sodium is transported in separate stainless steel pipes from the two IHXs to the SG top head through vertical inlet nozzles. The cold leg piping returns the sodium to the IHX. Two EM pumps, located in the SG facility, transport the sodium through the IHTS loops. The pump design is similar to the primary system pumps. 

Exhibit 4-27 illustrates how primary process considerations govern the elevation of the surface condenser and some of its auxiliary equipment. Because a pump is needed to remove the condensate from the hot well, the pump net positive suction head (NPSH) must be satisfied to operate satisfactorily. Vertical pumps are generally used in this application because the NPSH requirement is calculated from the bottom of the lower impeller for vertical pumps, compared with the centerline of the inlet nozzle for horizontal pumps. Setting the elevation of the inter-after condenser, usually located to the side of the suifice condenser, can be done with fewer restriaions. Ilie bottom of the inter-after condenser shell must not be more than 3 ft (900 mm) below the condensate return nozzle on the side of the hot well. The plant layout designer is then free to set the elevation as high as necessary. 

FIGURE 2. Two vertical inline pumps, located in the basement, circulate chilled water throughout the building. 

Other information pump type, required punip hydraulic horsepower, material of oonstritction, stress relief requirement, project pump specifications, pump position (vertical, horizontal, or inline), available utility such as cooling water, site conditions, pump location indoor or outdoor), minimum design metal temperature (MDMT), insulation requirement, steam out condition, etc. 

During operation the slurry is pumped under pressure into a vessel that is fitted with a stack of vertical leaves that serve as filter elements. Each leaf has a centrally located neck at its bottom which is inserted into a manifold that collects the filtrate. The leaf is constructed with ribs on both sides to allow free flow of filtrate towards the neck and is covered with coarse mesh screens that support the finer woven metal screens or filter cloth that retain the cake. The space between the leaves may... 

Fig. 5. Tentative mixed potential model for the sodium-potassium pump in biological membranes the vertical lines symbolyze the surface of the ATP-ase and at the same time the ordinate of the virtual current-voltage curves on either side resulting in different Evans-diagrams. The scale of the absolute potential difference between the ATP-ase and the solution phase is indicated in the upper left comer of the figure. On each side of the enzyme a mixed potential (= circle) between Na+, K+ and also other ions (i.e. Ca2+ ) is established, resulting in a transmembrane potential of around — 60 mV. This number is not essential it is also possible that this value is established by a passive diffusion of mainly K+-ions out of the cell at a different location. This would mean that the electric field across the cell-membranes is not uniformly distributed.

Submersible turbine pumps are a variety of vertical turbine pumps with the motor attached below the pumping unit. Water passes in through an intake port located between the motor and bowl assembly, then upward through the bowl stages to the surface through the pump pipe. Electric power is supplied to the motor by specially insulated wires. Submersible turbine pumps are manufactured for water supply and oil well usage by a wide variety of manufactures in sizes ranging from /3 to several hundred horsepower, and are constructed of materials suited for many chemicals. 

Vertical leveling screws spaced for stability shall be provided on the outside perimeter of the baseplate. They shall be located adjacent to anchor bolts to minimize distortion during the process of installation. These screws shall be numerous enough to carry the weight of the baseplate, pump, and drive train components without excessive deflection, but in no case shall fewer than six screws be provided. 

The horizontal pumps are available for capacities up to 900 m /h (4000 gahmin) the vertical in-line pumps, for capacities up to 320 m /h (1400 gahmin). Both horizontal and vertical in-line pumps are available for heads up to 120 m (400 ft). The intent of each ANSI specification is that pumps from all vendors for a given nominal capacity and total dynamic head at a given rotative speed shall be dimensionally interchangeable with respect to mounting, size, and location of suction and discharge nozzles, input shaft, base plate, and foundation bolts. 

Circulation and shear of the liquid in a vessel can be accomplished with external pumps and appropriate location of suction and discharge nozzles, but a satisfactory combination of vertical and lateral flows is obtained more economically by internal impellers, baffles, and draft tubes. Some general statements about dimensions, proportions, and internals of a liquid mixing vessel can be made. 

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